Automatic station selecting and tuning device for radio receivers and the like



March 21, 1950 J. LOLLI EI'AL 2,501,472

AUTOMATIC STATION SELECTING AND TUNING DEVICE FOR RADIO RECEIVERS AND THE LIKE Filed April 17, 1946 7 Sheets-Sheet 1 oo'oo J. LOLLI EI'AL ION March 21, 1950 2,501,472 AUTOMATIC STAT SELECTING AND TUNING DEVICE FOR RADIO RECEIVERS AND THE LIKE Filed April 17, 1946 7 Sheets-Sheet 2 lu ll J. LOLLI ETAL March 21, 1950 2,501,472 AUTOMATIC STATION SELECTING AND TUNING DEVICE FOR RADIO RECEIVERS AND THE LIKE 7 Sheets-Sheet 3 Filed April 17, 1946 NMV vlwli'riiiihili \M Nw mm ononoio w o 0 9 0 61 0 O O \7 \w 0 09 1030 0 o ozouoz .o

March 21, 1950 J. o| ETAL 2,501,472

/ AUTOMATIC STATION SELECTING AND TUNING DEVICE FOR RADIO RECEIVERS AND THE LIKE Filed April 17, 194a '7 Sheets-Sheet 4 March 21, 1950 J. LOLLI ETAL AUTOMATIC STATION SELECTING AND TUNING DEVICE FOR RADIO RECEIVERS AND THE LIKE 7 Sheets-Sheet 5 Filed April 17, 1946 March 21, 1950 J. LOLLI- ETAL 2,501,472

AUTOMATIC STATION SELECTING AND TUNING DEVICE FOR RADIO RECEIVERS AND THE LIKE Filed April 17, 1946 7 SheetS -Sheet 6 March 21, 1950 J. LOLLI ETAL 2,501,472

AUTOMATIC STATION SELECTING AND TUNING DEVICE FOR RADIO RECEIVERS AND THE LIKE Filed April 17, 1946 7 Sheets-Sheet '7 Patented Mar. 21, 1950 AUTOMATIC STATION. SELECTING AND TUNING DEVICE FOR RADIO RECEIVERS AND THE LIKE John Lolli andGene Papitto; Chicago Heights, 111.

Application-April'l'l, 1946,"Serial N; 662,670

4 Claims. (Cl.:250--20) The present invention relates to automatic station selecting and tuning devices for radio receivers, and is particularly concerned with the provision of an improved station selector for home radio. receivers, which is. adapted to energize suitable circuits at predetermined times so that a home radio receivermay be-automatically tuned at pre-selected times to receive broadcasts from such stations as are desired, the selected stations following one after another without-interruption and without any necessary attention on the part-of the user.

While the present devices. are; peculiarly adapted for selecting and tuning home radio receivers to desired stations, we'wish it to. be understood that the 'present'mechanism may be utilized for various different purposes, and parts of the mechanism are of general application and may be employed'in manydifferent arts.

One of theobjects of theinvention is the provision'of an improved station selector for home radio receivers by meansof which the user may, while a station is broadcasting, or at any earlier time, so adjust the elements of the device. that the radio receiver will be automatically tuned to the station or stationsdesired practically in:- stantaneously at the-time the adjustment is made or atsome future'selected: time-and so that the user may thereafter be provided with broadcast reception for every-fifteen minute period of the day and night'as he'desires, without interruption.

Another object of the invention is the provision of an improved mechanism of the class de-. scribed which permits the user to utilize manual tuning as and when desiredand which also permits the user'. to utilize push b'utton'tuning at any time he may so desire.

Another. object. of the'invention .is the provi sion of an improved mechanism of the class described including step-by-step means for moving the mechanism from its proper position for one fifteen minute period'oftime to the proper position for the next fifteen minute period of time, which mechanism positively holds the elements in the proper predeterminedxposition', and which permits thechange to. be madepractically instantaneously and exactly at the end' of each fifteen minute. period, with; an accuracy within a few seconds.

Broadcasts are frequently prefaced by means of commercial broadcasts, which may also 00- cupya portion ofthe period near. the'end of the fifteen minute period, and thus a few secends variation .ili'" the. time during whichv the mechanism;switchesa'from one station to another 'is not of th'e'utmost importance; but it is important that the timing be as. accurate as Dossible; as the commercial broadcast part may be very short, and no automatic station selector and tuning device whichdoes not operate at substantially the exact-beginning orzend ofa program would be satisfactory-tothe public.

Another object of theinvention is-the provision of an improved selector. and tuning, device for home receivers which-,is extremely simple, which can be manufactured at a very low. cost, which is positiveiand exact in its operation, which permits. themanual tuningby means of the usual rotating banks of condensers, but which does not employany movable condensers that require .exact adjustment, and which can be used forfla long period of time without necessity for repairiorreplacement of any of its. parts.

Another object of the invention, is the provisionof an improved timing-device of the class described; which. may be easily adjusted to correct.variationsimthetime setting of the clock, and which imposes no' great strain upon the motor of: the-clock, and which is readily adaptable to be used with existing installations to be combined with and made a part of. a radio receiver having the automatic timing and tuning mechanism built in the receiver.

Referring to the drawings, of which there are seven sheets,

Fig. 1 is a front. elevational view of a combined, radio receiver and. automatic station selecting, and tuning mechanism embodying the invention;

Fig.2 isarear elevationalview of the mechanism, from. which the details of. the radio receiver'have been omitted;

Fig. 3 is a'fragmentary;elevational view of the rotating; station selector member, which also accomplishes the automatic tuning;

Fig. 4 is a fragmentary top plan view of the step-by-step mechanism for moving the station selector from one, position-to :the other at the end of each fifteen minute broadcast period;

Fig. 5' is a wiring. diagram: of the electrical circuits employed in theautomatic tuning mechanism shown in connection with the manual tuning circuit fora conventional receiver;

Fig.;6 is a vertical sectional view taken on the plane of the line 6-6 of. Fig.- 2, looking in the direction of" the arrows, showing the way in whichthe station selector and tuner actuates the proper switches, and showing the details of construction and mode of support of this element;

Fig; Tis a fragmentary sectional. view taken on the plane of the line 1-1 of Fig. 2, looking in the direction of the arrows;

Fig. 8 is a fragmentary elevational view taken on the same plane as Fig. 6, showing a modified form of switch mechanism;

Fig. 9 is a fragmentary plan view of the mechanism shown in Fig. 6;

Fig. 10 is a fragmentary elevational view showing the position in which the step-by-step mechanism is at a time just prior to its actuation of the station selector member;

Fig. 11 is a diagrammatic elevational view showing the mechanism and circuit for another form of step-by-step mechanism adapted to hold the station selector in its proper position and to move it at an accurately predetermined time into its next position by means of a suitable motor and controlling switches;

Fig. 12 is another fragmentary ele'vational view of a modified form of step-by-step mechanism in which a solenoid is utilized for moving the station selector member, the parts being in the position which they assume just before the station selector member is moved another step;

Fig. 13 is a view similar to Fig. 10, showing the step-by-step mechanism of this embodiment in another position.

Fig. 14 is a fragmentary top plan view, showing the details of structure of the switch actuating members and their mode of engagement with the controlling pins;

Fig. 15 is a fragmentary elevational view taken on the plane of the line I-'l5 of Fig. 14, looking in the direction of the arrows;

Fig. 16 is a fragmentary sectional view of a modification of the selector plate by means of which the double plate of Fig. 14 may be eliminated and the pins given adequate support in a single plate.

Fig. 17 is a fragmentary sectional View taken through a modified selector plate, which is provided with improved pins adapted to be retained in the plate by means of a positiive latch.

Referring to Fig. '1, this is an elevational view, showing a radio receiver panel equipped with our automatic station selecting and tuning device. The panel or front wall of the cabinet is indicated by the numeral 20, and it is preferably provided with a round aperture 2! for exposing the selector mechanism, which is indicated in its entirely bythe numeral 22.

As the structure of the selector mechanism includes a centrally located opening 23, the assembly may include the speaker 24, the diaphragm of which (not shown) is located behind any suitable screen, or grille, indicated at 24 as being circular in shape and having an outer circular border 25 in front of and slightly overlapping the inner border of the bore 23 of the selector mechanism 22.

The assembly preferably includes a number of manual actuating members, such as the knobs 2B, 21, 28, and 29. The knobs 2T29 are preferably provided with similar pointers 30 for indicating any one of a plurality of positions. The panel or cabinet front 20 preferably includes a timing clock 3!, the dial 30 of which is exposed through a circular bore 32. The clock 3! preferably includes a second hand 33, a minute hand 34, and an hour hand 35.

The purpose of the knob 26, which has the indicia Clock" beneath it, is to adjust the minute hand 34 and hour hand 35 when the clock needs adjustment.

The panel or instrument front 20 preferably includes a tuning dial 36, with the usual indicia, kilocycles and/0r meters, and the scale divisions 31 and one or more single or double pointers 38, for sweeping over the scales and indicating the position of the manual tuning mechanism which is to be actuated by means of the knob 29, which bears the words Tuning dial beneath it. The mechanism for accomplishing the clock adjustment and manual tuning will be described later.

The knob 21 is for the purpose of controlling a multiple bank switch, and bears the word Switch underneath it and position indicia indicating Manual, Off, and Automatic. When this knob is turned to the position Manual, the bank switch which it controls is in position to permit manual tuning, and the circuits of the selector are disconnected from the automatic tuning condensers.

When the switch 21 is in the Off position, the radio, which is controlled by the device, is completely de-energized; and when the switch 21 has its knob 21 in the Automatic position, the circuits are conditioned for automatic station selection and automatic tuning, as distinguished from manual tuning.

The volume control knob 28 is provided with indicia, Soft, Medium, and Loud," and is the usual volume control member for a radio receiver.

Referring now to Fig. 2, this is a rear elevational view, in which the usual amplifying and detecting circuits of the radio receiver are diagrammatically indicated by the rectangle 39, the bank of tuning condensers being indicated diagrammatically by the numeral 40.

The tuning condenser shaft is indicated at 4|, and the driving pulley for the bank of condensers by the numeral 42. The tuning dial knob 29 on the front of the panel has a shaft extending backwardly through the panel, and is provided with a V pulley 43 of relatively small diameter, to be engaged by a belt 44. The tuning dial shaft 45, which carries the pointer 38, also con ries the V pulley 46 behind the panel, and the belt 44 engages pulleys 42, 43, and 46. Thus, as the tuning dial knob 29 is rotated, the rotatable condenser banks 40 are moved by the belt 44, engaging pulley 42; and simultaneously the belt 44 moves the pulley 46 to move the pointer 33 and to indicate the station adjustment.

Referring to the right hand side of Fig. 2, the minute shaft 41 of the clock 3| projects from the rear side of the clock, Where it is provided with a V pulley 48 for engagement with a belt 49.

The belt 49 also engages a V pulley 50 carried by the clock setting shaft 5| so that rotation of the knob 29 rotates pulley 50, moves belt 49, and rotates pulley 48 to adjust the minute hand 34.

The clock 3! is preferably of the synchronous alternating current type, but any type of clock may be employed which is adapted to tune the mechanism and to permit its proper adjustment, as described.

The mechanism of the speaker 24, which appears at the front of the panel 20, is indicated at the back by the numeral 52, and it is merely shown diagrammatically, as any type of suitable speaker may be employed.

Referring now to the wiring diagram of Fig. 5, this diagram shows the circuits which are controlled by the knobs 27 and 2B and also by the selector mechanism.

In this diagram 53 indicates the wall plug, which is adapted to be connected with any -means of conductors :58, 59 to'the circuit of the 7 standard wall socket that 1 is "energized with -.60

cycle, 110 volt electricity.

'i The line .conductorstb l, :55, whichleadfrom theconnector prongs 56, 551, are connected'zby --electric clock 3l,,which preferably operates continuously so that the selector is ready at any .timexto select the stations that have been previously designated by the user.

Assuming that the selector mechanism is to include five predetermined broadcasting stations and assuming that the radio receiver .has .an

,audio circuit and a radio frequency circuit, gtwo condensers of predetermined capacity are, re- .quired for tuning each station, in a receiver hav- :ing two variable tuning condensers.

,these are merely exemplary of the indiciathat are used all around the selector dial :60.

The outermost row of holes ti is for neutral purposes and for storing the pegs 61 (Fig. 6)

when no station is selected for that quarter hour. The circular series 52 of holes are, as indicated,

.for a certain station, which'may be WGN. Thus,

letters on the selectordial iii).

In the wiring diagram the three banks of mov- -:'for-'' connecting the adjustablebank condenser 68 :inthe radio receiver circuit which includes conductors 85, 86, so that manualtuning may be accomplished.

When the switch arm 1-8 .is in anintermediate vertical position engaging contacts'li'l, all circuits are broken, and neither manual nor-automatic tuning. can be accomplished.

:When the switch .isin position engaging'the contacts-182 andflfl of banks 15 on the back of the-dial, the knob?" on the front has its pointer pointing, to Automaticand tuning of this portion-ofthe radio receiver circuit is to .be accomplished-by means of the trimmer condensers, invent-which areshownconnected to the conductors QI andSE. "Therest of the trimmer condensers are indicated at 95, 96, 91, 98.

.'In order to tune sucha radio receiver by'means Lof'trimmer condensers, as many separate trimmer condensers are required for each station as there are-variable condensers in'the receivers. Thus,

"the banks lfiaand the. banks 1'! of contacts control circuits similar to those controlled by the contact bank 15.

The other trimmer-condensers are indicated by the numerals 99- to its and ltd-H18. These trimmer condensers are likewise connected toua common conductor I21, for the bank'lt and I28 for, the bank l l.

It should be noted that even though the switch controlledby knob LZIisconditiQned for automatic tuning byits positioning to contacts .82

and viii the circuit will, still be open at theindividualselector.switches-92,-93; andall of the able condensers are indicated by the numerals 68, 5t, and '10, and that these condenser banks are simultaneously adjustable is indicated by dotted lines ll-l3, connectedby the common actuating member, or dotted line 74.

The switch knob Zl controls three banks of switch contacts, indicated at l5, 15, 17, each being located to be engaged by a movable contact arm, which contact arms are generally indicated by the dotted lines l8, l9, and 80, joined by a common actuating member indicated by thedotted line 8 l.

The two outermost contacts 82, 83 are joined by means of a conductor 8% and have a common lead 85 interposed in the circuit of the radio receiver at the same point where the bank condenserGB is interposed; and this may be accomplished by grounding the lower conductor 86 on the receiver frame, as is often done.

The two middle contactssl are merely neutral open position contacts, The contact 88 of bank "i5 is connected by a conductor 89 to the movable condenser 68, while the other contact at of the bank i5 is connected to a common conductor Qi that leads to one of the contacts 92 of a multi- 'Manual tuning, and the switch 'is conditioned others of .the same type of Fig. 5, the contacts of which .will now be numbered.

Thus, .the ,fixed contacts of these individual selector switches 101 bank 15 are, indicated by the numerals Mil-4B. The fixed contacts oi'the individual selector switches are indicated bythe numerals lM--I I8.

The fixed contacts ofthe individualselector switches of the bank 1'! are indicated by the numerals I l9----l23.

Since it is necessary to use three fixed condensers for tuning each station, and there are five stations, three times five, or fifteen, fixed condensers are employed, as follows:

The fixed condensers and 99 and I M maybe those for tuning the-station WGN. Thefixed condensers 95, I00, and I05 may bethoselfor controlling the tuning of the station WMAQ. The fixed condensers '96, Iill, and I06 may be those for controlling the tuning of station WLS. ,The fixed condensers 9T, l02,-and Hll may-be those for tuning the station WBBM. The fixed condensers'98, H13, and let may-be those for controlling the tuningof the station WCFL.

While the trimmer condensers employed have been referred to as fixed condensers, this is--a relative term, as even such trimmer condensers permit adjustment of capacity. They are preferably of the type employing a'porcelain base and a pair of thin metal condenser plates mounted thereon and insulated by means ofomic'a or the like, the'prox-imity of these plates being controlled by means of a pressure screw adapted 'to be adjusted with a screw driver.

gem- 72 has a movable arm I25 adapted to be actuated in common with the arms 18, 19, 30, as indicated 'by the dotted line 8 I.

This bank I24 has suitable contacts adapted to cut off entirely the energization to the radio receiver, While the switching is being accomplished by the banks 15, 1B, 11 so that the energizing circuit may be re-established after each switching movement simultaneously with the establishment of the proper connections.

cludes a fourth set of contacts for connecting the receiver to the energizing line at the contacts I24. When a peg I 40 passes out from under one actuating member I41, for example (Fig. 6), the

circuit will be opened in all three stages to disconnect the tuning condensers, and also at the energizing line 54, which leads to the wall socket; but the clock, being in advance of the bank of contacts I24, it will continue to operate. A moment later another peg in a suitable aperture in the selector will come into engagement with the camming surface on the side of another or the same lever I41 or I48 (Fig. 6), closing suitable contacts in all three stages, and also closing the main contacts I24, which keep the receiver energized.

In some embodiments of the invention permeability tuning may be substituted for trimmer condenser tuning. In such case each trimmer condenser has substituted for it a tuning coil which has an iron core, and which coil accomplishes the proper tuning of the circuit.

Such tuning has the advantage that it does not drift or lose its adjustment, which happens more frequently with trimmer condenser tuning.

It will thus be observed that the knob 21 controls suitable banks of switches, which have contacts adapted to connect in circuit in the radio receiver, either the banks of rotatable condensers or the conductors which lead to individual selector switches, for each station, by means of which fixed condensers can be connected in the radio receiver circuit in the same position as the movable condensers are usually connected. The number of switches depends on the number of variable condensers in the chassis.

Thus, when the knob 21v is turned to Manual tuning, the ordinary rotatable condensers of the radio receiver may be rotated to tune in the station. When the knob 21 is turned to Automatic tuning, the rotatable condensers are cut out of the circuit with the knob 21 in this position, it is the closure of the individual station selecting and tuning switches, which are indicated by the numbers 92-423, which energize the receiver and tune the station. Simultaneous energization and tuning is accomplished for any station when its three trimmer condensers are simultaneously connected in circuit by three of the switches of the series 92, -123.

We shall now describe the mechanism by means of which this is accomplished.

Referring to Fig. 2, the back of the panel is preferably provided with a suitable supporting framework, such as a U-shaped standard I26, the legs of which are shown supporting some of the trimmer condensers 94I08, some being on the opposite side of this frame.

The panel or front wall supports on its rear side a plurality of roller brackets I29, I30, I3I,

I32,'which are secured to the panel by the screw bolts I33 passing through the brackets.

Each of these brackets may have an angular offset I34 Fig. .7 and a pivot flange I35, which has a shaft I38 riveted in it and pivotally supporting a flanged roller I31. The roller I31 engages the edge of the circular selector dial 22, and the flanges I38, 38 engage in front and back of this selector dial.

The rollers carried by brackets I29I32 are preferably equally spaced about the periphery of the circular dial plate 22, and thus they support it for rotation about the axis of this dial plate. The selector and dial plate 22 may be constructed of a sheet of transparent plastic, such as Lucite or Tenite, or it may be a metal plate or a phenolic condensation compound, but the transparent plastic plate is preferred, as it is more easily worked, durable in construction, and adapted to retain the selector pins 81 by frictional engagement with the holes.

Referring to Fig. 7, the pins 61 are preferably made of metal, and may be provided with an elongated cylindrical or slightly tapered shank Id!) terminating in a conical end portion MI, the point I42 of which is preferably rounded.

The length of the shank I40 is suflicient to extend completely through the selector dial plate 22 and another spaced plate I63, which may be utilized in the absence of sufficient thickness in the plate 22, both plates having aligned apertures.

The shank it!) may be provided with an annular tapered portion at IM to Urdu so that the pin may engage and be wedged into the front of the plate 22 by a slight twisting pressure.

The plate 22 may be made thick enough to provide adequate support for the pins 61 so that they will not give or bend from their proper axial position with respect to plate 22, but in some embodiments of the invention a secondary bracing plate I43 may be employed which is slightly smaller in size and provided with the same registering apertures for pins 61.

Bracing plate I43 may also be utilized as a driving member and may have its periphery provided with a multiplicity of regularly spaced slots I46, these slots being radially arranged and rectangular in elevation and being located accurately at angular distances corresponding to oneninety-siXth of the circumference.

The slots or notches I46 provide definite shoulders for engagement with a step-by-step and a stop mechanism by means of which the selector plate 22 is rotated step by step at the end of each quarter hour and definitely held in predetermined position throughout each quarter of an hour.

The pins 61 project through the back of the two plates 22 and I43 suffieiently to engage any one of a multiplicity of switch levers, indicated by the numerals M'I-ISI (Fig. 6). These switch actuating levers are pivotally mounted on the pivot bolts $52 on an upwardly extending auxiliary frame H35, in such a manner as to pivot on a horizontal axis and in such manner that the left ends of the levers MCI-I5! (Fig. 6) are in position to be engaged by the pin 61, the particular switch lever to be actuated depending upon the location of the pin 81 in the series of holes 62-66 (Fig. 3).

If the pin 61 is located in any of the series 62, it will be in position to engage the switch lever I41; and in this manner the pin 61 may be 10-- cated to actuate anyone aof .the switch levers The switch levers :I'41.I 5 I rare-preferably pr ming surface engaged :bythe pin shank tee .to

cam a lever I ll-IEI upward in Fig. 6 to close the switch contacts.

Thus, as the selector dial rotates a pin 61, which happens to be at the top, engages a-switch lever for that particularlluarter'hour for each step in "the rotation :of .the selector dial, and closes the proper circuits, indicatedin,Fig.r 5',-to tune the station :whichccrrespondsto the radial locationof the pin 61.

.Each switch lever Iii-455i controls fourpairs of contacts, thus establishing aclosed circuit for three trimmer condensers, which will tune the circuits of that :particular station, 1 and another pair of -,contacts ,fcr energizing the'circuit. For example, the switch lever I41 might close the circuit of trimmer-condensers ,94, ,99,-and IEl l to effect a tuning of station 'WGN by C1OSiIlg contacts at ;-92,-I:'M,:and H9. The contacts I24 are the :contacts :for energizing :the circuit.

Referring to; Fig. 6,--,each switch .lever 11414.5 I carries a transverse insulating bar I58, which carries three contacts for; engaging three contacts carried by the insulating ;b.ar I59 mounted on resilient springs I63.

Referring toFig. 3,-this is a similar viewof a modification, in Which-the contacts of the resilient relay .type are employed, ,each.;switchincluding a spring IBI and :another spring, #52 carrying contacts which are actuated by means of a cross bar I63 that closes three switches simultaneously.

Switch levers I l'I-I5I are-provided with their end bevel 5-51 so thatthe pins fi'l may be used to tune in the station by ;the push button method at any time, even when the'pin 61 is inserted in the holes, which are then opposite to the levers I41I5I3.

When thisis done, the pointed endIsI of the pin 61 engages the beveled end I51 of one of the levers and moves the :lever to closed, switch position without utilizing theside camming surface I56.

Thus'the present apparatus maybe used for instantaneous push button tuning at any time. The station selected maybechanged in .the midst of a quarter hour-period at the will of the operator. As only one pin is provided for each indial series of holes, only one station should be tuned in at once.

Referring to Fig. 14,'this fragmentary plan view shows the :two uppermost switchactuating members I41 and M8. The supporting column I55 is there seen to; bee substantially U shaped channel member, one flange {$4 of which pivotally supports the lever-M1, andthe other flange I65 of which pivotally supports'the lever I48.

The offsets .155 .in eachof these levers bring the beveled end portion 14? of, each lever into the same radial plane with respect to thepins 61.

By means of the offset portions IM and by the disposal of the end-portions; I 65 of; the, levers Mik l :5 I ,in the manner s hown,in 1 Fig. 14 more room is provided for the banksof switches. Th e number :of switches actuated by a cross bar I at is unlimited; and if there are more than two receiver stages, they may .be controlled also by the same switch. Thus, if there are three receiver stages, in Fig. '14, there are'for thelever I,41 four pairsof contacts, one..for=receiver,stageNo. 1, one for receiver stage. No. 2, and another for receiver stage No.13, and one .pairofacontacts for the current supply.

-Referring to lfig. 16,"this shows a modified form of station selector dial I61, which maybe molded with rearwardlyextending cylindrical lugs/I68 of such length thatv they provide the pins QIwith an elongated support in :the bores I 69,, which is practically equivalent to thetwo spaced points of support thatareprovided-by the plates 22 and I43.

In other embodiments of the invention 3 the I pl telfilmay befmadeas'thick as the distance from ;-the front of the-plate to the end of the lugs I58."

Referring to Figs. 2 ,1, and 10, these views show the step-by-steumechanism by means of which the station selecting and tuning plate-80 is rotated'by an angular distance "equal'to "one ninety-sixth of the one-revolution at the endof each fifteen minute period ,andpositively held in this position until the end of another'fifteen minute period.

It is of the utmostiiinportance tha his mechanism be accurate within a few seconds; otherwisean important partof the program .atthe beginning or end maybe missedjby theilistener.

rhelcioersa has its minutehand shaft 41 extending backwardlyof the. clock housing,v or it may have an auxiliary-shaft,suchlas the shaft 41, which moves atthesame rate as the minute hand, that is, the; shaft 41;makes,one complete rotation Per hour, and it :makcs one-quartcrof arotation every .fifteen-minutes w-ith the minute hand to the shaftyof which itmay be geared.

The shaft 41 may carry-*the pulley 48, which is used :to adjust-thegclockand correct its timing;

and in: addition to-the-pulley shaft 48,- theshaft I1 may carry -a;ca;m I10. The cam 16 includes four cam-mine TSHI'fQQES I 1 I, "each of which increases in I radius; from a minimum at the 5 point I12 to the point I13.

The point "I13 corresponds angularly to the end of a fifteen minuteperiod, panel the radial iii shoulders -I14 must 3 permit anzimmediate drop of a follower engaging this -cam,-when;the follower passes the point I13, inorderto, eficcta quick timing. I

and the follower has its ;;surface I18 preferably disposed .at-anangle whichrglves a clearance between the Suriace I118 and the points I13..on'

the caln so-thatswhenthe corner I19 of the *follower-passes the point-I13, the follower I15is fullyiclear, of the radial sho d r this-point otthcc fllxirhus th r s a abrupt. movement ofthe lever 15 hen the ;.cam totates to a :position; so that point I13 passes corner I19. Lever I16 is urged in a clockwise direction in Fig. by a tension spring I80, having one end hooked in the lever at I8I and the other end hooked-in a frame member I82 carried by the back of the panel. The lever I16 is thus constantly urged into engagement with the cam I10, which rotates counterclockwise.

The frame member I82 may be supported in spaced relation to the panel by a plurality of bolts I63, and may have a depending arm I84 located adjacent the plate I43. The arm I84 has an extension I85 overlapping the plate I43, but not extending far enough to interfere with pins projecting through the holes in the plate and extension I85 has a stub shaft I88 for rotatably supporting a pawl I81.

Referring now to Fig. 10, where these parts are shown on a larger scale, the pawl I81 is in the form of a bellcrank, having an actuating arm I88 beveled at I89 and provided with a radial surface I90 to provide a sharp corner I9I.

The pawl I81 has another arm I92, which is preferably disposed in overlapping relation to the plate I43, and the arm I92 carries an axially extending flange I93, preferably havin a beveled edge 94 adapted to be received in the slots I46.

The point of pivot I86 of arm I81 is on a line at right angles to the, radius of the slot I so that flange I93 moves into slot I with a minimum amount of clearance to hold the plate I43 in accurately predetermined position.

The pawl I81 may be engaged by a spring I95, which has a plurality of helical turns about the stub shaft or bolt I86, and has one end hooked in the supporting arm I84 and the other end hooked about the bellcrank arm I92, urging the pawl I81 into engagement with the plate I43.

The edge I94 of the stop flange I93 may project from the arm I92 toward the plate I43. The pivot bolt I86 may consist of a cylindrical headed member threaded into the flange I85. Thus the pawl I81 is adapted to hold the plate I43 when it is located in a slot I46.

The lever I16 may also carry a depending arm I96 provided with a peripherally extending slot I91. A shoulder bolt I98 extends through the slot I91 with its cylindrical portion, and has its shoulder engage a pawl I99 located behind the lever I16 in Fig. 10.

Thus the pawl I99 is mounted for pivotal and sliding movement on the lever I16, and the length of the slot I91 is equal to the travel of the arm I16 at this point when it is moved or permitted to move by the cam I10.

The pawl I99 has its upper end provided with a hole 200, in which a spring MI is hooked. The

other end of the tension spring 20I is hooked in the hole 202 of an arm 203 carried by a pawl actuating lever 204, further to be described.

The direction in which the spring 20I pulls the pawl I99 is such that it tends to pivot the lower end 205 of pawl I99 into engagement with the plate I43, and it tends to pull pawl I99, with its shoulder bolt I98, upwardly in the slot I91. 2 The lower end 205 of pawl I99 has a diagonally and upwardly extending transverse flange 208,

which has a beveled end 201 for engaging in the slots I46 on the plate I 43, toward which the engaging surface 201 of pawl I99 is urged.

The purpose of the pawl I99 is to advance the station selector step by step. As the cam I10 rotates its camming surfaces I1I engage the follower I19 and urge the lever I16 in a counterclockwise direction. A's-this is done, the pawl I99 moves downwardly from the slot I46, in which' it happens to be engaged, and is cammed out of this slot by the camming surface 208.

Thereafter the pawl I99 rides on the outer cylindrical surface 209 of the plate I43 until the beveled surface 201 drops into the next slot. Thus the rotation of the cam I10 has caused the lever I16 to be depressed until the pawl I99 has taken a new hold on the rotating plate I43; and when the follower I15 passes point I13 on cam I10, spring I pulls the lever I16 in a clockwise direction, tending to cause the pawl I96 to rotate the plate I43.

It will be recalled that this plate is held in a fixed position by the pawl I81; and therefore provision is made, by means of the pawl actuating lever 204, to release the pawl I81 when the lever I16 has traveled a predetermined amount.

The lever 204 is pivoted on the lever I16 by means of another shoulder bolt 2I0, having its cylindrical portion pivotally supporting the lever 204, and having its threaded portion threaded into the lever I16.

The pawl actuating lever 204 extends upwardly along the periphery of the plate I43 and has the lateral extension 203 for engagement with the spring 201, which urges this pawl in a counterclockwise direction. At its upper end the lever 204 has a laterally extendin flange 2 located to engage the edge surface I on the pawl arm I88, and the edge 2I2 of the flange 2 is so located that it can pass the corner I9! on the pawl I81.

The lever 204 preferably has another laterally extending flange 2I3 closer to the pivot 2I0 and provided with a threaded bore 2I4 for receiving a screw bolt 2I5. The screw bolt 215 may be secured in place by a lock nut, and has its end engaging the opposing surface of a stop flange 2I6 carried by an upward extension of the lever Thus the pivotal position of the pawl actuating lever 204 on the lever I16 is determined by the adjustment of the screw bolt 2I5 engaging flange 2H5, and the spring 28! urges the lever into this position. The screw bolt 2I5 may thus be used to adjust the flange, at which the edge 2I2 of the flange 2H will slide off the corner I91 of the pawl I81.

The operation of this part of the mechanism is as follows: When the lever I18 rides over a point I18 of the cam I10 and moves in a clockwise direction, and the pawl I96 pulls upward on the plate I43, tending to rotate it, the lever 284 also moves upward until the flange 2H engages the surface I90 and pivots the pawl I81 counterclockwise to remove its keeper I93 out of a slot I46.

The plate I43 is already under tension of the spring I88, tending to move the lever I'lB upward, and with it pawl I99 and plate I43. The release of the plate I43 by pawl I81 thus causes the plate to move upward; but, as the lever I16 and pawl actuating lever 204 move upward, the flange 2H rides off the point I9I and permits the pawl I81 to have its edge I94 ride on a cylindrical surface 289 of the plate I43..

Thus the pawl I81 is in position to snap into the next slot I46 to hold the plate I48 in this position for one quarter of an hour.

It will thus be observed that the clock mech anism is adapted to move the plate I43, and with it the station selector and tuning dial 22 step by step at the end of each quarter of an hour, and alsoto hold it in this position without possibility 15 of change except at a the proper time. The

strengthof the spring I86 is'suchthat it isistron-g enough to cause the dial plate 22 to rotatea-nd to cause the pins 6'! to engage the beveled surfaces !56 upon the switch levers to actuate the switch levers into closed position, as shown by Figs. 6 and 8.

The step by step mechanism provides a delayed instantaneous action for moving the plate I43.

The switch levers are held in closed position by the pins until the pin passes thelever which i it is engaging, after which the spring tension of the switch levers urges them to the open position.

This spring tension is provided by the spring contacts I62 '(Fig. 8) but in the embodiment of Fig. 6 springs are provided for urgingthe-v levers l4'|-l5l in a counterclockwise direction.

Referring to Fig. 11, this is a modification in which the rotating selector dial is contro led by a simpler type of electrically controlled mechanism. In this case the edge of the rotating plate 2H, which is otherwise similar to the plate 143,,is provided with radial slots .2l8ior receiving a holding member ill-6 of similar shape carried by an escapement mechanism.

'Betweenthe slots 2 It there is a concave cylin- Idricaledge port on 226, and the escapement member 22 I has the maior portion of its surface cylindrical at 222 for sl dably engaging the concave surface 226. In this case t e. shaft supporting the escapement member 22! rotates-once each quarter of an hour, and is suitably geared tnthe sha t 223 to accomplish ths. The shaft 223 is driven by the motor 26!, to which itis suitably gearedso that the escapement member 22!.rotates once each quarter hour.

The shaft 223 also carries a cam-2.24, having-a dwell 225 of larger rad us-andadapted to hold the switches 226 and 222' closed whenrthey-engage this dwell. The cam 224 also has .aidwell 228 of relatively smaller radius, which perm ts the switches 226 and 22? to remain open while they'engage this portion of the cam.

lhe cam 224 has an abrupt shoulder at 229,012 which the switches 22,6, 22'! pass as the cam rotates counterclockwise, and it has-a sloping camming surface-2653 by means of which the switches 226, I22! ride from the smaller radius dwell 224 to the'large radius dwell225.

The escapementmember 22! is :.-driven by a 'motor 23!, the energization conductors of which are .232 and 233. Conductor 262 extends to the line at 234, which is preferably energized with 6.0 cycle alternating 110 volt current, while the conductor is connected by conductor 235 to the fixed contact 236 of switch 227.

Conductor 223 is connected to'the movable contact 237 of switch 226. The cam 224 is driven by the motor 23! through the intermediary of gears 238 and 239.

This t ming device also includes a clock 240, which has a shaft 24! driving a cam 242. The cam'242 gradually increases in radius from the point 243, where'there is anabrupt shoulder244, the -maximum radius being outwardly of this shoulder at 245. l

The cam i242 and shaft 24 I may be-drivenffrom the minute hand shaft by means .ofgears: 246, 241; and the cam 242 controls a pair of switches 248, 242. The movable contact 256 :of switch 22'! is connected by conductor 25! to the movable contact 252 ofswitch246.

The switch 249 has another movable contact 253, which' is connected'to .the line conductor 254. 'The fixe'd contact 255 of switch 226 ,is con- :nected by conductor I256 to-the 'movable con- 14 tact225! oi'switch 248. The:othersmovablercom tacti258 of switch 248' is connected .byzconductor 259 to the line 254.

The movable contacts of the switches 248 and 242'have laterally turned end portions 260, 26!, 252, and 263-engaging the edge of cam242. These laterally turnedend portions or contact followers for'the cam are spaced from each other peripherally :of the: cam so :that oneafter another rides ofif the abrupt shoulder at 244.

When both. of the contacts of a. switch 249 or 248 are ridingon the cam at the same'radius, the switchesare open, whether it be a large or small radius. The switches248 and 252 are only closed momentarily as-thei cam rotates clockwise, when thezfiange 263 rides 01f the shoulder 244 first to close the switch;242, or the flange 266 rides off t e shoulder 244 before the flange 26! of. switch 248.

"Thus the cam :242 is adapted to close the circuits at the switches .248 and 249 only momentarily, after which the circuits are again, opened;

and there 'bei-ngtwo switches, this momentary .as follows: The clock escapement or Geneva movement memb-erq22l is rotated once at the end of each. quarter of an hour, this action taking place quite quickly, and the. lug 2H2 engaging in one of the arooves2l8 to move the plate 2!! one stepforward. 1 2

- Themember22! is driven by themotor 23 l, and through the intermediary of. suitable gearing the motor 23! drives the .cam 228. makes one-half turn; every fifteen minutes, and the switches.225..and 222 are used to .deenergize the motor 231. Eachziof these switches, however, is in series with theline and with one of the switches 248- and 1249. For exampla'the switch 2211s in series with the sw tch 249 controlled by the cam 242. The switch 226 is in series with the switch 248 controlled by the cam 242.

Thecam'242 makes one-half turn every fifteen minutes so that one orthe other of the switches .248, .249 is energized momentarily, and then deienergizedyat the end of each quarter hour period.

-Suppose, for-example, that the position of the abrupt shoulder 244 of cam 242 is approximately .as shown at the end of a quater-hour period. Then the'member .252 of switch .249 will pass .oifitheabruptshoulder 244 and come in contact with member-253 of switch 249, thus causing'a circuit to;close.

Now, since switch 22"! is in series with switch 249, it will :complete the c rcuit to the motor 23!, because the member 256 of switch 22'! is on the dwell surface of cam 225, which causes switch 122! to close its part of the circuit.

This :circuititoithe' motor being complete, the motor 23! will be energized, which then will cause member 22I to rotate onceito advance plate 2!! onesteoforward. This action of the motor, however, ;.causes the motor to de-energize itself, .zbecauseiasjitzdrives member 22! one complete revolution,.itsimultaneously drives .cam 228 onehalf revolution until abrupt shoulder. 229 comes opposite member 256 of switch 221, which will open and :break .circuit as member. 252 passes of]? shoulder 229.

.As pain 228 causesswitch 22! to. open, it at the same-time causes switch 226 to close, -preparing a: circuit-which willbecompletedby. switch 248 at .the end 10f; another quarterehour .LZQEIiQd.

Thus:.:.the.-plate;2 I]: is rotated. one step eachuquar- The cam .228

' 15 ter of an hour and is held in fixed position throughout the fifteen minutes, while the selected program is bein received.

Referring to Fig. 17, this shows the improved selector plate l! provided with an improved form of pin 219, with positive means 2?! for holding the pin in the plate. In this case the shank 212 of the pin is of the same shape previously described, and the head 213 may be similar in shape.

The shank 2'12 is provided with an aXial slot 214 communicating with a radial bore 2'15. The latching means for holding the pin comprises a light spring wire 2, which has an inwardly turned end 276 with a friction fit in the bore 215.

From the bore 215 the Wire has an upwardly extending hump 271 that engages the back of the plate 161 to hold the pin in place. Below the hump the slot 274 is sumciently deep so as to give the wire room in which to bend out of the way to permit the pin to be inserted or removed from the plate 167.

The hump in the drawings is purposely exaggerated to illustrate its action. When the pin is pressed into its bore, the wire 21! is flattened out, but it springs out behind the plate to hold the pin in place. The hump 271 is cam shaped 'or sloped at each side so that it is automatically flattened out while the shank of the pin passes through the bore of the plate.

In this case it is unnecessary to provide the front of the panel with a means for preventing removal of the pins. When the latching pins are not used, the front of the panel is preferably provided with an extraplate 289 hingedly mounted at 28! and latched shut at 282 on the opposite side, this plate being annular in shape and Wide enough to cover all of the pins to prevent their unauthorized removal.

The plate 289 also has an aperture in the middle for the speaker 24, or in some embodiments of the invention the clock may be placed in the center.

Referring now to Fig. 12, this in another modification, in which the plate [43 is provided with a step-by-step actuating mechanism similar to that described in Fig. 2; but in this case the load is taken from the clock and placed upon a solenoid 283.

In this case the clock shaft, which makes one revolution every fifteen minutes, may drive a cam 284, which has an abrupt shoulder 285 and an increasing radius from the abrupt shoulder 285 around the cam to the outer part of this shoulder.

The cam 284 is adapted to actuate a pair of spring switch arms of the switch 286. The switch arm 28? has a short engaging end portion 288 riding on the cam 284. The switch arm 289 has a longer flange290 riding on the cam 284.

The contacts carried by switch arms 281, 289 are connected by conductors 29f, 292 to the coils of the solenoid 293 and to the line at 292, 293 of current suitable for energizing the solenoid. The lever 294, which is pivoted on the frame at 295, is similar in operation to the lever H6 previously described in Fig. 10.

The retaining pawl 29B is similar to retaining pawl l8? previously described, but is different in shape, and engages an adjustable stop screw 29'! carried by the frame. The pawl actuating lever 298 operates like the pawl actuating lever 204 of Fig. 10, but has its lower end engaging an adjustable stop screw 299 carried by lever 294.

The pawl 309 is similar in operation to the pawl I99 previously described, and is urged upward by spring 39L The lever 294 has a laterally turned flange 392 above the solenoid plunger 393, which engages this flange and moves the lever 294 upward whenever the solenoid is energized.

Aside from being actuated by a solenoid, the operation of this mechanism is the same as that of Fig. 10. The cam 294 only closes the switch 286 momentarily, when the flange 29H rides off the shoulder 285 at the end of each quarter hour. A few seconds later the flange 288 rides off the shoulder 285, and the switch 286 is again opened up. During this time the solenoid has been energized momentarily and has moved the plate I43 one step forward to select and tune the mech-' anism of the receiving set for the next station.

Referring to Fig. 13, this in another mechanism similar to that of Fig. 10, but having further refinement in the adjustment of the lower pawl. In this case the lever 394 is similar to the lever 119 of Fig. 10, but carries a roller follower 395 for engaging the cam H0.

The pawl 396 operates similar to the pawl I99 of Fig. 10, but instead of having a pivot post and slot connection, it is pivotally mounted at 391 on a lever 398, which is pivotally mounted at 399 on the lever 394. The pivotal motion of the lever 308 on the lever 394 performs the same function as the slot l9? in Fig. 10, but the amount of this pivotal movement is adjustable by means of a set screw 310, carried by lever 3G8, engagin flange 3 on lever 394.

The pawl 31 2 in this mechanism operates like pawl l8"! of Fig. 10. The pawl actuating lever 3E3 operates like the lever 204 of Fig. 10, but is provided with a separate spring, urging it toward the pawl 3l2. Likewise the pawl 396 has a separate spring urging it into the notch-engaging position.

It will thus be observed that we have invented an improved radio station selector and tuner by means of which the user of a radio receiving set may select the same one or different stations for any quarter of an hour of the day, and having selected any one of these predetermined stations, the mechanism will automatically turn off the station from which broadcast is being received, and select a new station, or continue the same station at each quarter of an hour, as prede termined by the user.

The present mechanism is very simple, and can be manufactured at a very low cost. Its operation is positive, and it not only moves the station selector to the next place positively, but it also holds it positively in that place.

The selection of a new station and tuning of the new station is accomplished almost momentarily within a few seconds and accurately at the end of the quarter hour. The correction of the time of the clock may be accomplished at any time by the user.

The selector may be changed to any of the other stations at any time by the user, even while the program is being received. The present push pull controlling pins may be inserted as desired, either while the station is on or before or after the station is tuned.

The present apparatus may be used for receiving sets having any number of different stages. Suitable arrangements are also made for per mitting a separate manual tuning by means of an adjustable condenser plate.

While we have illustrated a preferred embodiment of our invention, many modifications may be made without departing from the spirit of the 17 invention, and we do not wish to be limited to the precise details of construction set forth, but desire to avail ourselves of all changes within the scope of the appended claims.

Having thus described our invention, what we claim as new and desire to secure by Letters Patent of the United States, is:

1. A station selector and tuner for a radio receiver, comprising a support, a multi-stage radio receiver carried by said support, a fixed trimmer condenser for each radio station and for each stage of the receiver, each condenser being connected in circuit with one of the receiver stages and with a station switch, a common actuating member for actuating all of the switches controlling the trimmer condenser for the various stages for each station, said actuating member being laterally beveled to provide a camming surface, said receiver including a speaker carried by said support, and said speaker registering with an opening in an annular station selector member, grooved rollers carried by said support, said annular selector member having its edges mounted in the grooves of said rollers, said selector member having a ring of holes through it for each station and a hole in each ring for each quarter hour of the day, a plurality of headed pegs mounted in said holes and projecting backwardly from said annular selector member in position to engage predetermined common switch actuating members at their lateral camming surfaces as the annular selector member rotates, each peg actuating a predetermined common actuating member at the beginning of a predetermined quarter hour period, means for rotating the annular selector member step by step at the end of each quarter hour through an arc equivalent to one quarter hour on the annular selector member, and means for positively holding the annular selector member from moving in either direction during the periods of time between its step by step movements.

2. A station selector and tuner according to claim 1, in which the common actuating members for the trimmer condenser switches are provided with beveled ends and the pegs may engage these beveled ends when inserted through a hole which is already in registry with the common actuating member in question, to cam the common actuating member into closed switch position by engagement of the end of the peg with the camming surface on the end of the common actuating member.

3. A station selector and tuner for radio receivers according to claim 1, in which the pegs are recess-ed to provide space for a retaining spring provided with a hump for engaging a retaining shoulder on the back of the annular selector member.

4. A station selector and tuner for radio receivers according to claim 1, in which the step by step mechanism is controlled by a switch driven by a clock, and in which the means for positively holding the station selector against rotation in either direction as aforesaid, comprises a circular formation on a Geneva gear adapted to rotate in a complementary, concave, circular formation in the edge of the annular station selector.

JOHN LOLLI. GENE PAPITTO.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,356,915 Fisher Oct. 26, 1920 1,937,099 Stewart Nov. 28, 1933 2,073,417 Fox et al Mar. 9, 1937 2,097,330 Kiena Oct. 26, 1937 2,234,668 Davenport Mar. 11, 1941 2,257,537 Samburg Sept. 30, 1941 2,337,568 Owens Dec. 28, 1943 2,346,623 Stewart et al Apr. 11, 1944 

